I write a lot of C# and it has a really useful way to query large collections of data, called LINQ.

Although JavaScript arrays have querying capabilities through map, reduce, filter but the limitation is they process the entire array before going to the next step, meaning if you do a map then a filter the whole collection goes through map process before it starts filtering. This can be a problem with large data sets, it can take a while.

The advantage of LINQ is that it uses lazy execusion, each item goes through the whole pipeline before the next item is processed. So if you have a large data set you can easily process subsets of the data and break early.